A U.S. sailor scrubs the flight deck of the aircraft carrier USS Ronald Reagan to remove potential radiation contamination on March 23, 2011 while operating off the coast of Japan during Operation Tomodachi.

Eight U.S. Navy sailors who took part in rescue operations following last year’s devastating earthquake and tsunami in northeastern Japan filed a damages suit last week against Tokyo Electric Power Co., the operator of the stricken Fukushima Daiichi nuclear plant, for not revealing dangerous levels of radiation. The sailors claim Tepco failed “in reckless disregard” to properly inform them of the actual radiation contamination levels, giving them a “false sense of security,” according to the suit filed in a California federal court.

The group is seeking $10 million in compensation and $30 million in punitive damages for fraud, failure to warn them of the health risks, for the plant’s defective safety designs, deceptive business practices and public nuisance. The group also wants the company to create a $100 million fund to cover their medical costs.

Tepco declined to comment Thursday, saying it hadn’t been informed of the suit or seen the filing.

The company also faces a raft of lawsuits at home from shareholders, residents who lived near the plant, and businesses for damages caused by the accident.

Investors launched a $67 billion lawsuit against company executives in March for dismissing warnings of a possible tsunami. Earlier this month, a group of residents with homes inside the 30-kilometer evacuation zone around the plant sued for mental anguish and forced relocation.

The eight sailors with the aircraft carrier USS Ronald Reagan were dispatched as part of a large-scale tsunami relief effort called “Operation Tomodachi.” The six-week operation ultimately included 20 ships and nearly 20,000 personnel. One of the eight sailors also named her daughter, born seven months after the March 11 disasters, as a plaintiff in the suit.

The suit says Tepco and the government “conspired and acted in concert” to create an “illusory impression” that the extent of the radiation that leaked from the plant was at levels that wouldn’t pose a threat so as to promote the company’s interests and those of the government.

The suit says Tepco’s and the government’s assurances led the crew to believe it was “safe to operate within the waters adjacent” to the plant site “without doing the kinds of research and testing that would have verified the problems.”

The International Atomic Energy Agency and other nuclear experts have criticized Japan for withholding information during the crucial early hours of the crisis, leaving many residents in the dark about matters like radiation levels. The government subsequently acknowledged its clumsy handling of what turned out to be the world’s worst nuclear accident in a quarter century.

The sailors claim they “must now endure a lifetime of radiation poisoning and suffering which could have been avoided.” The filing doesn’t specify the sailors’ medical conditions before or after March 11.

The plaintiffs claim the government is also at fault for misrepresenting the situation and saying there was “no danger of radiation” to the ship or its crew, and that everything was “under control.”

In an October report, Tepco for the first time admitted it had knowingly avoided implementing safety measures to protect the plant.

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